This invention relates to articulated doors comprising rectilinear, horizontally joined panels capable of articulately opening and closing and, more particularly, to weatherproof, shock-resistant and readily serviceable continuous flexible hinges for articulated vehicular doors subject to harsh "over-the-road" conditions.
Articulated doors find application in many areas, including garage doors and as doors in over-the-road vehicles. This application is concerned not with articulated garage type doors, which operate in a relatively static environment, but rather with articulated vehicular doors for over-the-road cargo containers, semi-trailer vans and truck bodies which operate in a radically different, dynamic environment. Such vehicular doors are designed to move in parallel tracks from an "overhead" or open, horizontal position below the roof of the container, van or truck body to a "closed" vertical position meeting the floor of the container, van or truck when the container is closed. Articulated doors used in such dynamic environments are subject to devastatingly harsh treatment including heavy jostling and harmonic motion when travelling over-the-road, frequent opening and closing at stops each time goods are moved in and out, as well as nearly continuous exposure to the elements. Dynamic seals which resist the jostling and harmonic motion, the frequent and rough use and the exposure to the elements are needed in such dynamic environments.
Hinges of the type typically used today in such dynamic environments include conventional metallic hinges bolted to pairs of adjacent door panels which naturally require periodic lubrication and, more importantly are subject to friction and wear under the harmonic stresses of over-the-road vibrations. Such hinges typically protrude from the inside surface of the door into the vehicle body, and can hang up on cargo, preventing opening of the door and damaging goods which move against the door during shipment. Additionally, it is time-consuming and expensive to remove these hinges in order to replace damaged door panels.
Conventional hinges used in such overhead doors do not absorb shock. Also, they do not provide a moisture barrier, which is particularly important in shipping moisture-sensitive goods. Furthermore, even if a separate moisture barrier were installed between adjacent door panels, dynamic stresses at through-holes for the fasteners holding the hinges in place still prevent a durable dynamic seal. Additionally, the through fasteners themselves, since they are directly exposed on the outer surface of the door, are subject to corrosion and subsequently cause deterioration at fastener holes where vibration stresses are absorbed.